BackErase example for C++ 5.0 and later

This example turns off repainting of the background, then zooms out to show the effect when repainting.

m_LEADRasterView1.SetBackErase(FALSE);
m_LEADRasterView1.SetAutoRepaint(FALSE);
m_LEADRasterView1.SetAutoScroll(FALSE);
// Calculate the values to zoom out by 10 percent and center the image.
m_LEADRasterView1.SetDstWidth(m_LEADRasterView1.GetDstWidth() * 0.9f);
m_LEADRasterView1.SetDstHeight(m_LEADRasterView1.GetDstHeight() * 0.9f);
m_LEADRasterView1.SetDstTop((m_LEADRasterView1.GetScaleHeight() - m_LEADRasterView1.GetDstHeight()) / 2);
m_LEADRasterView1.SetDstLeft((m_LEADRasterView1.GetScaleWidth() - m_LEADRasterView1.GetDstWidth()) / 2);
// Set the clipping area to the same as the destination rectangle
m_LEADRasterView1.SetDstClipWidth(m_LEADRasterView1.GetDstWidth());
m_LEADRasterView1.SetDstClipHeight(m_LEADRasterView1.GetDstHeight());
m_LEADRasterView1.SetDstClipTop(m_LEADRasterView1.GetDstTop());
m_LEADRasterView1.SetDstClipLeft(m_LEADRasterView1.GetDstLeft());
// Redisplay the image
m_LEADRasterView1.ForceRepaint();